US117936A - Improvement in saw-mill carriages - Google Patents

Description

UNITED STATES APATENT OFFICE.

IMPROVEMENT IN SAW-MILL CARRIAGES.

Specification forming part of Letters Patent No. 117,936, dated August S, 1871.

To all whom fit may concern:

Beit known that I, GEORGE SELDEN, of Erie, county of Erie, State of Pennsylvania, have invented certain new and useful Improvements in Saw-Mill Carriages,.of which the following is a full, clear, and exact description, reference being' had to the accompanying drawing making part of this specification, in which- Figure l is a perspective view of a carriage embodying my improvements. Fig. 2 is a vertical transverse section; and Fig. 3 is a detached view of the I-rack stick, showing the manner in which it is spliced.

Similar letters of reference denote corresponding parts in all the figures.

My invention relates to that class of carriages Which is usually employed in connection with circular saws, the lo g being supported upon headblocks mounted upon independent trucks, and connected with each. other at their front end by a girt or stringer in such manner that they can be adjusted longitudinally thereon in order to accommodate logs of varying length, the rear ends ofthe head-block being' connected with each other by means of the set-shaft employed for thrusting the knee forward. The invention consists of certain features of construction which will be hereinafter fully explained.

In the drawing, A A represent the sills or bedpieces upon which. the carriage is supported. Sill A is provided with a l'lat track of the ordinary description. B is a wrought-iron A-rail, the form of which is shown plainly in Figs. il and 2.' C C are the head-blocks, but, as the knees which move the log forward on them form no part of this invention, they are not shown in the drawing. Any

usual or desired form of knee may be employed. The front ends of these head-blocks are mounted upon trucks or chairs D provided with grooved wheels E adapted to run upon the track B. F F are dummies or supplemental carrying-blocks, one at each end of the carriage, designed to support the ends of the log. G is an intermediate stiiening-block. This block is not so high at its front end as the dummies and the head-blocks, and is not designed to sustain any portion ofthe weight of the log, but merely to strengthen the carriage. His a wrought-iron I -girt or stringer, serving the double purpose of adj ustably connecting the head-blocks and dummies with each other and of furnishing a support for the cogged rack knees.

I, which is bolted to the lower flange of the girt, as at f1?, Figs. l and 3. h are splicing-plates, by means of which the sections of girt H are secured to each other. J J are hangers or pockets attached to the lower sides of the head-blocks and dummies. They are provided with in-turnin g' lips j jl, which inclose and engage with the upper iian ge ot' girt H, thus forming a connection which will slide freely on the girt, so that the blocks and dummies can be adjusted thereon, as the length ofthe log may indicate, as will be readily understood without further explanation. The pockets attached to the head-blocks and central supporting-block are usually constructed as shown in Fig. 2-that is, the lip jl is made rem ovable and adjustable, being secured to the body of the pocket by a bolt or bolts, j?, one upon each side ot theblock. By this construction I am enabled to remove the gi rt without sliding it through these pockets, and can also clamp the blocks to it, as it is necessary to do in order that the cogged rack may propel the carriage. K are carrying-wheels, upon which the rear ends of the blocks and dummies are mounted. L is a set-shaft similar to those gen erally employed in this class of carri ages for operating the devices for actuating the By preference I provide the dummies with sleeves or elongated hubs l, through which the set-shaft passes, for the purpose of giving a longer bearing-surface,as the dummies, for the sake of lightness and strength, have their vertical walls made quite thin, and when desired the headblocks may be provided with similar hubs, although, as they are usually built with double walls, it will not generally be found necessary.

I am aware that dummies have been employed in combination with the old style of frame carriages, but in that construction they formed no part ofthe frame-work, and bore no part in supporting it against th e racking and twisting strain 5 whereas, in my carriage they not only support the ends oi' the log, but form an integral part oi' the frame-work, and stitien and strengthen it materially, so much so that I have found it advantageous to add a third one, placed between the headblocks, but not designed to bear any part ofthe log. These dununies also enable me to use amueh lighter girt and rack, as they shorten the distance between the bearing-points. I do not, therefore, claim them broadly.

The use of the hollow wrought-iron track is also a great improvement upon the cast-iron track now in common use, because it can be rolled in almost any desired lengths, and is not liable to be broken by the concussion produced by rolling a log upon the carriage, and, owing to its being holloW,'the quantity of iron required for its oonstruction is not so great as to make it too eXpensive.

The form of the I-girt adapts it particularly for combinationwith the head-block and cogged rack, as it is very stili, to resist strainboth vertically and laterally, and can be spliced by means of the bars or plates, as shown, without interfering` with either bolting,` on the rack or sliding the blocks over any portion of its upper liange from one end to the other.

In ease the splice shown should not be sufficiently strong, the plates may be made to extend from the upper to the lower iian ge, and the lips of the pockets made shorter so as to pass the plates, as this arrangement will not impair or ai'ect the eiciency of the pockets.

Having now described my invention, What I claim as new, and desire to secure by Letters Patent, is

l. In combination With the head-blocks C U,

`the I-girt H, pockets J, and rack I, substantially as set forth.

2. In combination With the head-block C, rack and string-er H, and set-shaft'L, the dummies F, substantially as set forth.

GEO. SELDEN.

Witnesses:

W. J. F. SIDDELL, F. F. CLEVELAND.

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